METERING DEVICE FOR GRANULAR MATERIAL AND DISTRIBUTION MACHINE HAVING METERING DEVICE

Abstract

The invention relates to a metering device (5) for granular material, in particular seeds and/or fertilizer, where the metering device (5) comprises a metering housing (9) having at least one inlet (8) and at least one outlet (11) for the granular material and two side walls (10) that are arranged spaced from one another, where a metering wheel (13) with end faces (13a) each pointing toward the side walls (10) is arranged between, firstly, the inlet (8) and, secondly, the outlet (11), and between the side walls (10), that are arranged spaced from one another, on a shaft and is connectable in a force-fit manner to the latter and can be driven to rotate by the shaft in a metering direction (D), where the metering wheel (13) is associated with blocking means (14) which are configured to block the metering wheel (13) against the transport of granular material in a direction opposite to the metering direction (D) from the inlet (8) to the outlet (11) and/or in the metering direction (D) from the outlet (11) to the inlet (8), and a plain wheel (15) is arranged at each end face (13a) of the metering wheel (13) and extends between the end face (13a) and the side wall (10) in an unfastened manner on the shaft, where a sealing element (16) is arranged on both sides between the respective end face (13a) of the metering wheel (13) and a side surface (15a) of the respective plain wheel (15) pointing toward this end face (13a).

Claims

1. Metering device (5) for granular material, in particular seeds and/or fertilizer, where said metering device (5) comprises a metering housing (9) having at least one inlet (8) and at least one outlet (11) for said granular material and two side walls (10) that are arranged spaced from one another, where a metering wheel (13) with end faces (13a) each pointing toward said side walls (10) is arranged between, firstly, said inlet (8) and, secondly, said outlet (11), and between said side walls (10), which are arranged spaced from one another, on a shaft and is connectable in a force-fit manner to the latter and can be driven to rotate by said shaft in a metering direction (D), where said metering wheel (13) is associated with blocking means (14) which are configured to block said metering wheel (13) against the transport of granular material in a direction opposite to said metering direction (D) from said inlet (8) to said outlet (11) and/or in said metering direction (D) from said outlet (11) to said inlet (8), and said metering device (5) comprises a filling member comprising at least two plain wheels (15) arranged in an unfastened manner on said shaft, where a plain wheel (15) is arranged at each end face (13a) of said metering wheel (13) and extends between said end face (13a) and said side wall (10), where a sealing element (16) is arranged on both sides between said respective end face (13a) of said metering wheel (13) and a side surface (15a) of said respective plain wheel (15) pointing toward this end face (13a).

2. Metering device (5) according to claim 1, characterized in that said sealing element (16) is configured as an at least approximately semicircular sheet metal part (16), that said sheet metal part (16) extends like a segment of a circle from said inlet (8) in said direction of rotation (D) of said metering wheel (13) toward said outlet (11) between said side surface (15a) of said respective plain wheel (15) and said end face (13a) of said metering wheel (13).

3. Metering device (5) according to claim 1, characterized in that said sealing element (16) is configured as a ring-shaped sheet metal part (16), that said sheet metal part (16) extends in engagement around said shaft in a circular manner between said side surface (15a) of said respective plain wheel (15) and said end face (13a) of said metering wheel (13).

4. Metering device (5) according to claim 3, characterized in that said ring-shaped sheet metal part (16) comprises a recess (16a) in the region of said outlet (11) from said metering housing (9), that said metering device (5) is configured by way of said recess (16a) to eject granular material that is jammed between said sheet metal part (16) and said end face (13a) of said metering wheel (13).

5. Metering device (5) according to at least one of the preceding claims, characterized in that said plain wheels (15) each comprise a recess (15c) in the region of said outlet (11) from said metering housing (9), that said metering device is configured by way of at least one recess (15c) to eject granular material that is jammed between said plain wheel (15) and said end face (13a) of said metering wheel (13).

6. Metering device (5) according to at least one of the preceding claims, characterized in that at least one plain wheel (15) comprises a, preferably resilient, spring element (17) acting in the direction of said side walls (15a) between said sealing element (16) and said side surface (15a) facing said sealing element (16).

7. Metering device (5) according to claim 6, characterized in that said spring element (17) is configured as a ring-shaped foam member (17), that said foam member (17) extends in engagement around said shaft in a circular manner between said side surface (15a) of said plain wheel (15) and said sealing element (16).

8. Metering device (5) according to at least one of the preceding claims, characterized in that said metering wheel (13) is arranged at least approximately in the middle between said side walls (10) that are arranged spaced from one another.

9. Metering device (5) according to at least one of the preceding claims, characterized in that said sealing elements (16) and/or said plain wheels (15) comprise devices (15b, 16b) by way of which said sealing elements (16) are fastened in a positive-fit manner to said respective plain wheel (15).

10. Metering device (5) according to at least one of the preceding claims, characterized in that said end faces (13a) of said metering wheel (13) are trough-shaped.

11. Metering device (5) according to at least one of the preceding claims, characterized in that said filling member comprising said at least two plain wheels (15) is formed integrally.

12. Metering device (5) according to at least one of the preceding claims, characterized in that said metering wheel (13) and said sealing elements (16), said plain wheels (15), and/or said at least one spring element (17) have an almost identical outer diameter.

13. Metering device (5) according to at least one of the preceding claims, characterized in that said blocking means (14) comprise at least one elastic sealing lip (14a).

14. Metering device (5) according to at least one of the preceding claims, characterized in that said blocking means (14) comprise at least one brush element.

15. Distribution machine (2) for spreading seeds and/or fertilizer comprising a storage container (3) for seeds and/or fertilizer and at least one metering device (5) associated with an outlet opening of said storage container (3), characterized in that said metering device (5) is formed according to at least one of the claims 1 to 14.

Description

[0028] Further details of the invention can be gathered from the description of the examples and the drawings. The drawings are showing in

[0029] FIG. 1 a distribution machine formed as a single grain sower arranged behind an agricultural tractor in a perspective view,

[0030] FIG. 2 a metering device with a closed metering housing in a perspective view,

[0031] FIG. 3 the metering device according to FIG. 2, where the metering housing is open and reveals a first embodiment of a metering wheel in a perspective view,

[0032] FIG. 4 the metering wheel removed from the metering housing according to FIGS. 2-3 in a perspective view,

[0033] FIG. 5 the metering wheel according to FIGS. 2-4 in an exploded view,

[0034] FIG. 6 the metering wheel according to FIGS. 2-5 in a cross-sectional view,

[0035] FIG. 7 the metering wheel according to FIGS. 2-6 in a longitudinal sectional view,

[0036] FIG. 8 a second embodiment of a metering wheel removed from a metering housing in perspective view,

[0037] FIG. 9 the metering wheel according to FIG. 8 in an exploded view, and

[0038] FIG. 10 the metering wheel according to FIGS. 8-9 in a longitudinal sectional view.

[0039] A distributing machine configured as a single grain sower 2 arranged behind an agricultural tractor 1 can be seen in FIG. 1. Single grain sower 2 in direction of travel F at its front end comprises a storage container 3 for seeds and/or fertilizer and at its rear end a plurality of sowing units 4 arranged side by side transverse to direction of travel F. Storage container 3 saddled onto the frame of single grain sower 2 is formed to be funnel-shaped and at its lower end comprises outlet openings which are covered by sowing units 4 and each of which is associated with a metering device 5 for granular material. The number of outlet openings or metering devices 5, respectively, in this single grain sower 2 corresponds to the number of sowing units 4, where one respective metering device 5 is configured to dispense material stored in storage container 3 in metered quantities and is connected to a sowing unit 4 via dispensing lines (not shown). In this way, fertilizer and/or seeds from storage container 3 can additionally be distributed to sowing units 4.

[0040] It is also conceivable that storage container 3 comprises a number of outlet openings with metering devices 5 that differs from the number of sowing units 4. In the event that there are more metering devices 5 than sowing units 4 present on single grain sower 2, it is conceivable that one sowing unit 4 is supplied by more than one metering device 5 and/or at least one metering device 5 is switched off or the associated outlet opening is closed by a shut-off valve 6. In the event that there are more sowing units 4 present than metering devices 5 on single grain sower 2, it is conceivable that one metering device 5 supplies several sowing units 4 with material. A split dispensing line can be used only be way of example for this purpose.

[0041] Sowing units 4 are arranged side by side transverse to direction of travel F on a frame of single grain sower 2 and each carry two material tanks 7a, 7b, a first material tank 7a preferably for seeds, and a second material tank 7b preferably for seeds and/or fertilizer. First material tank 7a is connected to a concealed separating device for the individual delivery of seeds for distributing the seeds on an agricultural area during operation. A metering device 5 is likewise associated to second material tank 7b, which can also be referred to as a micro-granulate tank, for dispensing the stored material.

[0042] Such a metering device 5, as is used on storage container 3 and on second material tank 7b, can be seen in FIG. 2 in a view isolated from single grain sower 2. Metering device 5 is arranged via shut-off valve 6 to an outlet opening of storage container 3 or material tank 7b. Shut-off valve 6 can be moved at least between a closed and an open position, so that granular material can enter metering device 5 via an inlet 8. Metering device 5 comprises a closed metering housing 9. Metering housing 9 is also formed substantially by two mutually spaced, oppositely disposed side walls 10 between which an outlet 11 extends at the lower end, and a housing flap 12. A dispensing line can adjoin outlet 11 so that the material delivered by metering device 5 is distributed at the desired location.

[0043] Housing flap 12 can be folded down about a pivot axis so that metering housing 9 is open and reveals a view onto a first embodiment of a metering wheel 13, as shown in FIG. 3. In this position, metering wheel 13, which is arranged between inlet 8 and outlet 11 and at least approximately in the middle between side walls 10 that are arranged spaced from one another, can be removed from metering housing 9. FIGS. 2-7 show a first embodiment of metering wheel 13, where metering wheel 13 is shown in a view removed from metering housing 9 in FIGS. 4-7. A second embodiment of metering wheel 13 can be seen in FIGS. 8-10 in a position removed from metering housing 9.

[0044] Metering wheel 13 comprises end faces 13a facing side walls 10 and, in the position installed in metering housing 9, is arranged on a shaft, not shown, to which it can be connected in a force-fit manner. For this drive connection to the shaft, metering wheel 13 comprises a hub 13b and can then be driven to rotate in a metering direction D. Metering wheel 13 is further associated with blocking means 14 which are configured to block metering wheel 13 against the transportation of granular material in a direction opposite to metering direction D from inlet 8 to outlet 11 and in metering direction D from outlet 11 to inlet 8. Disposed to the right and the left of metering wheel 13, more precisely on each end face 13a of metering wheel 13, is a plain wheel 15 which extends between the respective end face 13a and the respective side wall 10 of metering housing 9. Plain wheels 15 together form a so-called filling member and thereby fill the space between metering wheel 13 and side walls 10 within metering housing 9 at least approximately, so that granular material is guided exclusively at least approximately in the region of metering wheel 13 from inlet 8 to outlet 11 through metering housing 9. Plain wheels 15 are arranged in an unfastened manner on the shaft, not shown, so that they are not co-driven when metering wheel 13 is in rotation. In the present embodiments, the filling member is configured in two parts. Plain wheels 15 can be releasably fastened and plugged together to form the filling member. In an embodiment not shown, the filling member is formed integrally, i.e. is made as one piece.

[0045] A sealing element 16 is likewise arranged on both sides of metering wheel 13 between respective end face 13a and a side surface 15a of respective plain wheel 15 facing this end face 13a. In this first embodiment of metering wheel 13, sealing element 16 is configured as a ring-shaped sheet metal part and extends in engagement around said shaft in a circular manner between side surface 15a of plain wheel 15 and end face 13a of metering wheel 13.

[0046] Sealing element 16 is intended to prevent granular material from jamming between driven metering wheel 13 and stationary plain wheels 15 and is arranged rotationally fixed on plain wheel 15 in a positive-fit manner by way of devices formed on plain wheel 15 as an anti-rotation 15b lock by way of fastening grooves 16b on sealing element 16 and corresponding devices engaging in fastening grooves 16b. When metering device 5 is in operation, sealing element 16 is consequently at a standstill. Should individual grains nevertheless get jammed between metering wheel 13 and a plain wheel 15, then sealing element 16, which is presently configured as a ring-shaped sheet metal part, comprises a recess 16a in the region of outlet 11 from metering housing 9. The otherwise flat, circular contact between sealing element 16 and end face 13a of metering wheel 13 is interrupted by recess 16a so that space is locally exposed for jammed material and metering device 5 is configured by way of recess 16a to eject granular material that is jammed between sealing element 16 and end face 13a.

[0047] Blocking means 14, provided to prevent the unintentional escape of granular material from metering device 5, are arranged in the region of inlet 8 on the upper side of metering wheel 13 and in the region of outlet 11 on the lower side of metering wheel 13 and comprise an elastic sealing lip 14a. In an embodiment not shown, blocking means 12 can alternatively or additionally comprise at least one brush element. As the cross-sectional view of metering wheel 13 in FIG. 6 shows, sealing lips 14a nestle flexibly against metering wheel 13. In the region of inlet 8, granular material is prevented from being transported from inlet 8 to outlet 11 in a direction opposite to metering direction D, both when metering wheel 13 is stationary and when it is driven in metering direction D. In the region of outlet 11, sealing lip 14a likewise nestles flexibly against metering wheel 13 and then prevents granular material from being transported in metering direction D from outlet 11 to inlet 8 when metering wheel 13 is stationary. When metering wheel 13 is driven, the granular material is entrained in and/or between conveying elements 13c arranged on the outer surface of metering wheel 13 in the wedge between sealing lip 14a and metering wheel 13 and, after passing through between metering wheel 13 and sealing lip 14a, trickles into outlet 11. Provided for fastening blocking means 14 are two respective screws 14b with which the former can be affixed in bores provided on plain wheels 15, as shown in FIGS. 4 and 5.

[0048] In order to enable simple assembly of metering device 5, in particular metering wheel 13, a spring element 17 configured as a ring-shaped foam member, in particular a foam spring, is arranged between sealing element 16 and side surface 15a of two plain wheels 15 facing sealing element 16. Spring element 17, presently configured as a ring-shaped foam member, engages around the shaft, not shown, in a circular manner and extends between side surface 15a of respective plain wheel 15 and respective sealing element 16. Spring element 17 acts in the direction of side walls 10 and has a spring travel of at least approximately one millimeter so that sealing element 16 is held by way of spring element 17 securely in abutment against end face 13a of metering wheel 13. The first embodiment of metering wheel 13 can be seen in a longitudinal sectional view in FIG. 7. Due to the fact that plain wheels 15 abut against side walls 10 and spring element 17 is supported on side surface 15a of plain wheels 15 and acts in this direction, sealing element 16 is held in an elastically resilient manner, as described above, in abutment against respective end face 13a of metering wheel 13. The sealing of metering wheel 13 is thus improved and fewer grains jam between metering wheel 13 and sealing element 16. Furthermore, spring element 17 compensates for manufacturing tolerances of the components arranged on the shaft (not shown), namely metering wheel 13, plain wheels 15, and sealing elements 16, in that spring element 17 is either compressed or expanded. The assembly of metering device 5 and in particular of metering wheel 13 is thereby particularly facilitated.

[0049] As FIG. 7 also shows, end faces 13a of metering wheel 13 are trough-shaped. A particularly small friction surface then arises between end face 13a and adjacent sealing elements 16 transverse to metering direction D during operation, i.e. to the rotational motion of metering wheel 13. Firstly, this reduces the torque required to drive metering wheel 13 and, secondly, defined contact conditions arise between metering wheel 13 and sealing element 16 which allow sealing element 16 to act as a sacrificial component for metering wheel 13. The material combination of metering wheel 13 and sealing element 16 is selected such that sealing element 16 wears first, i.e. serves as a wear partner This has the advantage that metering wheel 13 has to be replaced less often in the course of regular maintenance work than sealing element 16, where sealing element 16 is very inexpensive to obtain. As a result, maintenance costs are saved in a simple manner.

[0050] A second embodiment of metering wheel 13 can be seen in FIGS. 8-10 in a position removed from metering housing 9. Parts with the same effect are denoted with the same reference numerals as in the first embodiment. This metering wheel 13 is also associated with a plain wheel 15 and a respective sealing element 16 on both sides, as shown in FIG. 8. Sealing elements 16 are affixed in a positive-fit manner on plain wheels 15 and both parts are stationary when metering wheel 13 is in rotational operation by way of hub 13c.

[0051] The second embodiment of metering wheel 13 is shown in an exploded view in FIG. 9. In this embodiment, sealing elements 16 are configured as an at least approximately semicircular sheet metal part and extend from inlet 8 in the direction of rotation of metering wheel 13, i.e. metering direction D, in the shape of a segment of a circle to outlet 11 between side surface 15a of respective plain wheel 15 and end face 13a of metering wheel 13. This embodiment has the advantage that there is even less friction created between metering wheel 13 and sealing elements 16, since they extend substantially only over the part of the circumference of metering wheel 13 in which the granular material is transported.

[0052] In order to prevent grains from jamming between metering wheel 13 and plain wheel 15, plain wheels 15 are each provided with a recess 15c in the region of outlet 11 from metering housing 9. Recesses 15c create an enlarged spacing between metering wheel 13 and respective plain wheel 15, so that metering device 5 is configured by way of recesses 15c to eject any granular material that is jammed between respective plain wheel 15 and end face 13a of metering wheel 13.

[0053] As FIG. 10 as well as FIG. 7 further show, metering wheel 13 is at least approximately as wide as one of plain wheels 15. Furthermore, metering wheel 13 and sealing elements 16, as well as plain wheels 15, have an almost identical outer diameter. Spring elements 17 of first embodiment also have an outer diameter at least approximately identical to plain wheels 15, sealing elements 16, and metering wheel 13, as shown in FIG. 7.

LIST OF REFERENCE CHARACTERS

[0054] 1 agricultural tractor [0055] 2 single grain sower [0056] F direction of travel [0057] 3 storage container [0058] 4 sowing assembly [0059] 5 metering device [0060] 6 shut-off valve [0061] 7a,b material tank [0062] 8 inlet [0063] 9 metering housing [0064] 10 side walls [0065] 11 outlet [0066] 12 housing flap [0067] 13 metering wheel [0068] 13a face end [0069] 13b hub [0070] 13c conveying element [0071] D metering direction [0072] 14 blocking means [0073] 14a sealing lip [0074] 14b screw [0075] 15 plain wheel [0076] 15a side surface [0077] 15b antirotation lock [0078] 15c recess [0079] 16 sealing element [0080] 16a recess [0081] 16b fastening groove [0082] 17 spring element